Increased insulin binding to erythrocytes in diabetic ketoacidosis: normalization with insulin therapy.
We studied insulin binding to erythrocytes in eight male type I diabetic patients in diabetic ketoacidosis (DKA) before and 24 h and 5 days after low dose insulin treatment. Mean specific [125I]insulin binding in DKA (mean +/- SEM, 13.3 +/- 0.6%) was significantly higher than values 24 h and 5 days after treatment (10.7 +/- 0.7% and 9.6 +/- 0.4%, respectively; P less than 0.001). These values after treatment were similar to those of 15 age-matched normal males (10.5 +/- 0.4%) and 6 controlled type I diabetic patients (10.1 +/- 0.7%). The affinity constant (Ka = 2.26 +/- 0.12 10(9) M-1) was significantly higher in DKA patients than in normal subjects (1.75 +/- 0.15 10(9) M-1) or type I controlled diabetics (1.55 +/- 0.15 10(9) M-1; P less than 0.01). Insulin binding correlated inversely with arterial pH (r = -0.80; P less than 0.001; n = 8). These results indicate an increase in specific [125I]insulin binding to erythrocytes in DKA, which is due to elevated receptor affinity (but not receptor numbers) and is reversible with treatment.
D000328:Adult; D016883:Diabetic Ketoacidosis / Q000097:blood / Q000188:drug therapy*; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000097:blood* / Q000627:therapeutic use; D007700:Kinetics; D008297:Male; D011972:Receptor, Insulin / Q000378:metabolism
D007328:Insulin; D011972:Receptor, Insulin